Internet Protocol TeleVision (IPTV) is a multimedia content delivery system in which multimedia content is delivered from servers to terminal equipment using the architecture and networking methods of the Internet Protocol (IP) suite over a packet-switched network infrastructure, such as the Internet and broadband Internet access networks. As used herein, terminal equipment includes the equipment necessary to render the multimedia content to users, such as a TV display screen, as well as any equipment necessary to receive the multimedia content from the network, such as a set top box (STB). IPTV systems supplement and sometimes are deployed alongside, or integrated with, traditional multimedia content delivery systems, such as radio frequency broadcast, satellite broadcast, or cable television (CATV) distribution. In general, all such systems are referred to herein as multimedia content distribution networks.
One known and increasingly popular service offered to subscribers of multimedia content distribution networks is the ad hoc distribution of multimedia content to individual users, on specific request. In some aspects, such as where the multimedia content comprises conventional movies, this service is known as Video on Demand (VoD). However, in general, the ad hoc distribution of multimedia content on request extends beyond movies, and includes multimedia content such as short video clips (e.g., YouTube® videos), non-real-time IPTV video streams, audio content (e.g., music, podcasts), and the like.
Providing the instantaneous, ad hoc distribution of multimedia content on request to user can place large demands on the multimedia content distribution network. Such demand is largely user driven and can therefore be hard to predict. Thus the load on a multimedia content distribution network can vary drastically, leading to poor utilization of network resources and possibly negative user experience of the distribution service if the network becomes overloaded.
One user phenomenon, which has become more prevalent in the age of increasing social connectivity, is user “swarming” behavior, wherein a large number of users request the same content within a short time period. For example, users may recommend certain multimedia content, or even simply announce that they have requested or are viewing it, via social network resources (e.g., Twitter®, Facebook®), or by conventional communication channels such as wireless or conventional telephone, Short Message Service (SMS, also known simply as “texting”), Instant Messaging (IM), email, and the like. Due to such a recommendation/announcement, which itself may spread “virally” among a large number of users, other subscribers to the multimedia content distribution network may request the same multimedia content, at roughly the same time. This results in a large number of individual streams (e.g., IPTV unicast streams), placing a high instantaneous load on the network, and resulting in the inefficient, duplicative distribution of the same content along numerous separate channels, very closely aligned in time (i.e., near-simultaneously).